In Japan, onion is mainly produced in Hokkaido. The quality of onion has been improved by breeding or crossing, and the production is increasing. Although cooking and proceeding properties of the onion have been reported in a few papers, the cultivars used in these papers are often unclear. Therefore, we employed 13 cultivars of onion currently cultivated in Hokkaido, and studied on individual cooking and proceeding properties. The results obtained were summarized as follows; All cultivar of onion bulb were levels of solid contents (9-11%) and reducing sugar (4-5 %) showed suitability of processing to saute and powder. (2) Brix percent of onion bulbs were 7-11%. (3) Phenol contents were 150mg/100 g in red type, and 70-100mg/100 g in yellow type. The cultivars which contain high phenol were evaluated with that it is bitter when it was sauted. The correlation was established between phenol contents and color value (a* and b*) of onion bulb, the green and yellow degree was high for onion containing high phenol. But phenol contents did no affect to color of sauted onion. (4) Pyruvate production was 5-9μmol/ g, this was divided into medium pungency. There was the positive correlation between pyruvate production and pungency, and negative correlation between pyruvate production and sweetness. There was no correlation between sweetness and free sugar, Brix, solid content.

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The mechanisms of gelatinization and retrogradation in Katakuri (Erythronium Japonicum DECNE) starch were investigated by differential scanning calorimetry (DSC). Potato and edible canna starches were also used in order to compare the difference in thermal properties of Katakuri starch. The gelatinization and retrogradation of starch-water systems with different in water contents (W_c) and thermal histories were measured by DSC. Non-freezing water content (W_nf), which was strongly restricted by starch molecules and which was not freezed until-150°C, was calculated from the enthalpies (ΔH) of phase transition of sorbed water and W_c. It was found that W_nf increased with increasing W_c and leveled off at W_c more than 6.0 g/g. The gelatinization temperatures (T_α) changed in the order of Katakuri < Potato < Canna. While, the enthalpies of gelatinization (ΔH_α) and the amount of W_nf changed in the order of Katakuri > Canna > Potato. These results suggest that Katakuri starch molecules have bulky structure compared with other starches of Potato and Canna.

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Banana and 'Hebezu' citrus fruits were exposed to various oxygen levels (5-100%) at 20°C. Rates of respiration and ethylene production were induced in both banana and 'Hebezu' citrus kept under high O₂ atmospheres (O₂ >21%). Respiration and ethylene production increased with the increasing of O₂ level in storage atmosphere. Banana stored in O₂ concentration above normal air developed the peel color to yellow stage, 90 degrees of hue angle, faster than those in normal air and low O₂ atmospheres, while the degreening in 'Hebezu' citrus stored in high O₂ levels did not advance over the control fruit. Low O₂ atmosphere (5 and 10%) was effective in suppressing respiration and ethylene production in both fruits, and the degreening was also delayed. Banana stored under low O₂ atmosphere remained unripe for 27 days and the normal ripening was found after transfer to air storage. Banana fruit in 10% O₂ ripened faster than those in 5% O₂. Total sugar content of banana after reaching full yellow stage in both low and high 02 atmospheres was slightly different from the control fruit, except the content in 80 and 100% O₂ treated fruits which was significantly lower than other treatments. Citric acid content of high O₂ treated 'Hebezu' citrus fruit maintained higher than control and low O₂ treated fruits. Soluble solid content in all storage conditions increased from the beginning except for 100% O₂ treated fruit, which showed the significantly lower content than other treatments and maintained the content as recorded at the initial.

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Postharvest application of 35-90% ethanol is reported to remove astringency and improve sweetness of banana. In order to determine the specific pattern and localization of gene expression, banana fruits were treated with 60% ethanol and control and then the total RNA extracted from the banana was hybridized with the RNA probe of ACC oxidase gene. When the representation of MAACO1 mRNA (encoding banana ACC oxidase) was compared with peel and pulp signal in control and 60% ethanol-treated banana, the pulp showed clearly higher representation than the peel in 3 days after the treatment and that in 6 days in control. These results indicated that the induction of internal ethylene in ethanol treated-banana regulated primarily MA-ACO1 gene expression in pulp and then the expression regions transferred to the peel. The expression of MA-ACO1 gene coincided roughly with the increase in ethylene production and the amount of mRNA in total RNA was also confirmed to increase.

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When food-spoiled bacteria, Pseudomonas fluorescens and Pseudomonas putida survived in pure water for a long time, their characteristics were compared with them of parents. Eight strains of Pseudomonas fluorescens and 8 strains of Pseudomonas putida were used for this experiment. Growth and some characteristics were investigated on these strains. When strains survived in pure water were directly inoculated to nutrient broth, their growth patterns were almost same with their parent strains. Strains survived in pure water at different temperature showed the same results with their parent strains on nutritional requirement, hydrolysis Tween 80 and casein, and characteristics of NF-18 and API ZYM. These results would show a putrefactive mechanism of food by these strains survived in poor nutritional condition.

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Components in Yuba easily change because soybean milk is heated for many hours during the process of Yuba production.It is reported that composition in soybean milk remarkably change during the course of Yuba production by heating, and that browning of Yuba is accelerated with increasing step of the production of Yuba.In consideration of above reports analysis of the components in Yuba was performed in order to elucidate the mechanism of its browning.Therefore, it is supposed that the mechanism of Yuba browning results form a Maillard reaction of saccharides with amino acid, the oxidation of lipids and the influences by metallic ions.The direct addition of the glutation (GSH), which is a tripeptide with SH-group having an antioxidant activity, to soybean milk was effective for the browning prevention of Yuba.

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The composition of cell fusion vegetable “Yamagata midorina” was investigated comparing with its parental “Yamaga Seisai” and “Chinese cabbege”, harvested from the same field in the same season in the year 2000. The vitamin content of three variety vegetables was investigated dividing with “leaf blade” and “leaf stalk and midrib”. There were much β-carotene, vitamin B1, vitamin B2 and vitamin C in “leaf blade” of the 3 variety vegetables. Three variety vegetables accumulated most quantities of the vitamin content in “leaf blade”. Contents of 13-carotene, vitamin B2 and vitamin C in “leaf blade” of “Yamagata midorina” were close to those of “Yamaga Seisai”. Content of vitamin B1in “leaf blade” of “Yamagata midorina” was intermediate between “Yamaga Seisai” and “Chinese cabbege”. Therefore, when nutrition guidance is educated to people, it is able to use of “Yamagata midorina” as a colored vegetable.

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